Exactly what I was going to say, no extra light but extra dark to make the change...

Don't forget to leave the fans on during the dark, it still gets hot after lights out + daytime temps = bad
redtails Reviewed by redtails on . Switching From Day to Night Lighting--Important Question! My plants are at third week of 12/12 flowering, and doing well. But because of rising heat (and an incomplete ventilation system), I'd like to switch to night lighting. My primary question is this: I know the best way would be gradually change the on/off times (like an hour or two difference each day). But I was wondering if I could simply run them through their twelve-hour cycle today, keep the lights on (but on low) through the night, and then turn them off tomorrow morning. But Rating: 5